The past half-year has been a dismal period for emerging-market bond investors. The pain began in May, when the Federal Reserve signaled that it may soon taper its massive bond-buying program. As prices for U.S. bonds dropped and yields shot up, money simultaneously flooded out of emerging-market bonds. For 2013 the total return (including interest payouts) for mutual funds specializing in emerging-market bonds was -6.9% as of mid-December, much harsher than the -1.4% return for the Barclays U.S. Aggregate Bond Index. But the selloff, say many experts, has now gone too far -- leaving investors with some compelling reasons to add emerging-market bonds to their fixed-income portfolios.